The present invention relates generally to a device and method for the treatment of atherosclerotic disease, and more particularly, to a device and method which utilizes the collateral blood flow of the Circle of Willis to aid in the extracting of an obstructed vessel supplying blood to the brain.
Atherosclerotic disease of the internal carotid artery is the most common reason for stroke. Atherosclerotic plaques form on the inner lining of the blood vessels supplying blood to the brain, and over time enlarge and become friable. Typically, a stroke occurs when small flecks of plaque break loose, travel with the blood into the brain, and lodge in an end vessel. By lodging in an end vessel, the clot prevents blood from passing through to the brain tissue supplied by the vessel. Without blood, the brain tissue will die within minutes.
Most flecks of plaque that result in clots spontaneously breakdown and cause only a temporary occlusion of blood, and thus reversible symptoms. This is termed a Transient ischemic Attack (TIA) and is a warning for an impending stroke. Because of the warning provided by a TIA, numerous patients are identified each year prior to a full stroke. Once identified, either because of a TIA or other symptoms, patients typically undergo a traditional surgical removal of the plaque. This procedure is termed a Carotid Endarterectomy (CEA) and basically involves opening the internal carotid artery, removing the plaque, and closing the vessel with suture. In order to open the internal carotid artery without the patient bleeding to death, the internal carotid artery must be clamped. While the vessel is clamped, the patient will be dependant on collateral blood flow from the other three vessels supplying blood to the brain, and an open Circle of Willis, to get blood to the part of the brain usually supplied by the clamped artery.
As with any major surgical procedure, there exists a certain amount of inherent risk to the patient. However, the major risk of a CEA is, ironically, a stroke because of the small microscopic flecks of plaque that remain in the vessel. The problems arising from the surgical intervention of a CEA have created strategies to repair the narrowing of the carotid artery without such surgical intervention. One such strategy involves the use of catheters to deploy stents that open the vessel and plaster the plaque against the vessel wall. Although such a procedure is significant in that the patient does not require surgery or general anesthesia, again the major risk therein is a high stroke rate. This happens due to the catheter and stent breaking off pieces of the friable plaque which are then carried directly into the brain.
In view of the aforementioned needs and the shortcomings of the prior art, it is therefore an object of the present invention to provide a system which overcomes the deficiencies of the current practices whereby a device and method is provided for the treatment of atherosclerotic disease.
Accordingly, it is a general object of the present invention to provide a new and improved catheter device and method.
It is a more specific object of the present invention to provide a device and method for the extracting of an obstructed vessel without surgical intervention.
Yet a more specific object of the present invention is to provide a catheter device and method which utilizes the collateral blood flow of the Circle of Willis to aid in the extricating of the obstructed vessel supplying blood to the brain to help prevent stroke.
The invention is directed to a vascular catheter assembly comprising an elongated tubular catheter body having an inner lumen to receive a guide wire and an expandable member near its end. A channel member having expandable members near both ends is slidably engaged to the catheter and includes a passageway defining an inner channel lumen.